Created by Khalil Klouche and aimed at small children, Knock Knock is a playful calculator which allows calculation on the wood surface by knocking and will give back the answer using the same knocking tone. Components include Arduino board, contact microphones and solenoids.

The device was designed for the exhibition “Touch!” at MUDAC (Museum of design and contemporary art) in Lausanne in 2012. It was also featured at Lift conference in 2013 and on Nouvo on RTS (Swiss TV). Khalil is a masters student in Media Design at HEAD-Geneva.